5.1 Top, Middle, & Base Notes: Understanding Volatility in Formulation

Introduction: Why Understanding Fragrance Notes is Important?

Every perfume is composed of different layers of scent, which evolve over time. These layers are categorized into top, middle, and base notes based on their volatility—how quickly they evaporate and become noticeable. Understanding these notes helps in creating balanced, long-lasting, and well-structured perfumes.

Key Concepts:

✔ Volatility → How quickly a fragrance component evaporates.
✔ Sillage → The scent trail left behind.
✔ Longevity → How long the fragrance lasts.

The Fragrance Pyramid: Structure of a Perfume

A perfume unfolds in three stages over time:

1️⃣ Top Notes (Head Notes) – First Impression

🔹 Definition: The most volatile (fast-evaporating) components, detected within the first 5–15 minutes after application.
🔹 Purpose: Provide freshness, brightness, and an initial burst of scent.
🔹 Common Aroma Chemicals:

• Citrus Notes → Limonene (from orange, lemon)
• Aromatic Notes → Linalool (from lavender)
• Green Notes → Cis-3-Hexenol (from fresh-cut grass)

✅ Example: A perfume with Lemon (Limonene), Bergamot, and Lavender (Linalool) will have a fresh, uplifting opening but fade quickly.

2️⃣ Middle Notes (Heart Notes) – The Body of the Perfume

🔹 Definition: Less volatile than top notes, lasting 2–4 hours after application.
🔹 Purpose: Provide the main character of the fragrance. They appear once the top notes start fading.
🔹 Common Aroma Chemicals:

• Floral Notes → Geraniol (from rose), Hedione (jasmine-like)
• Spicy Notes → Eugenol (from clove), Cinnamaldehyde (cinnamon)
• Fruity Notes → Methyl Anthranilate (grape, orange blossom)

✅ Example: A perfume with Rose (Geraniol), Jasmine (Hedione), and Cinnamon (Cinnamaldehyde) will have a rich floral-spicy heart after the citrusy top notes fade.

3️⃣ Base Notes – The Long-Lasting Foundation

🔹 Definition: Least volatile, lasting 4+ hours to several days.
🔹 Purpose: Provide depth, warmth, and longevity to the fragrance.
🔹 Common Aroma Chemicals:

• Woody Notes → Iso E Super (soft, woody), Ambroxan (amber, musky)
• Musk Notes → Muscone (natural musk), Galaxolide (clean musk)
• Sweet Notes → Vanillin (vanilla), Coumarin (tonka bean)

✅ Example: A perfume with Sandalwood (Santalol), Musk (Galaxolide), and Vanilla (Vanillin) will leave a warm and sensual trail for hours.

Practical Example: Creating a Balanced Perfume Formula

Objective:

Blend a simple fragrance using carefully selected top, middle, and base notes to demonstrate the concept of volatility.

Ingredients:

• Top Notes (Fast evaporating – 30%)

  • 10% Lemon Oil (Limonene)
  • 10% Bergamot Oil (Linalool, Limonene)
  • 10% Eucalyptus (Eucalyptol)

• Middle Notes (Moderate evaporating – 50%)

  • 20% Rose Absolute (Geraniol)
  • 15% Jasmine (Hedione)
  • 15% Clove (Eugenol)

• Base Notes (Slow evaporating – 20%)

  • 10% Sandalwood (Santalol)
  • 5% Vanillin
  • 5% Musk (Galaxolide)

✔ Total: 100% Perfume Concentrate

Step-by-Step: Blending and Testing the Formula

Step 1: Measuring Ingredients

✔ Using a precision scale, weigh each aroma chemical according to the formula.
✔ Mix them together in a glass beaker.

Step 2: Dilution in Alcohol or Oil

✔ Add the perfume concentrate to Ethanol (for a spray perfume) or Fractionated Coconut Oil (for an oil-based perfume).
✔ Typical dilution: 20% fragrance oil + 80% alcohol/oil.

Step 3: Aging & Maturation

✔ Store the mixture in a dark, cool place for 2–4 weeks to allow blending.

Step 4: Testing on Blotters & Skin

✔ Apply on a fragrance blotter and observe how each note evolves over time.
✔ Test on skin to check longevity & projection.

Observations & Learning Outcomes

🔹 First 15 min: The citrus notes dominate, giving a bright, fresh start.
🔹 After 30 min – 2 hours: Floral and spicy heart notes become noticeable.
🔹 After 4+ hours: Woody, musky, and vanilla base notes provide warmth and longevity.

Final Conclusion: Why Understanding Fragrance Notes is Important?

1️⃣ Knowing volatility helps in balancing how a fragrance unfolds over time.
2️⃣ Each note has a purpose: Top notes for freshness, middle notes for character, and base notes for longevity.
3️⃣ Blending different aroma chemicals strategically ensures a harmonious fragrance.
4️⃣ Testing on blotters and skin helps to adjust the formula for better performance.

💡 Next Experiment:
Try adjusting the ratio of top, middle, and base notes to see how it affects the fragrance longevity and projection! 🔬👃✨